I could make up a RD set with the Cajón but there is so many different beats.
I suppose I could make up a Sw set and a Ev set with a lot of variations to choose from ?
There are a lot of Cajón Kontakt and soundfonts that you could use with RB drum midi to get the beat you need, there's also loops.

Here's some freebies you could try:
http://www.sonic-cat.com/cajon-free/

http://www.musicradar.com/news/tech/free-music-samples-download-loops-hits-and-multis-217833/95

http://www.cajonroot.com/cajon-samples